A radio access method and a radio network for cellular mobile communication (hereinafter referred to as “Long Term Evolution (LTE)”, or “Evolved Universal Terrestrial Radio Access (EUTRA)”) are under study in the 3rd Generation Partnership Project (3GPP). In LTE, an Orthogonal Frequency Division Multiplexing (OFDM) scheme is used as a downlink communication scheme. In LTE, a Single-Carrier Frequency Division Multiple Access (SC-FDMA) scheme is used as an uplink communication scheme. In LTE, a base station device is also referred to as evolved NodeB (eNodeB) and a mobile station device as user equipment (UE). LTE is a cellular communication system in which the area covered by the base station device is divided in a cellular pattern into multiple cells. A single base station device may manage multiple cells.
In LTE, the mobile station device transmits a sounding reference signal (SRS) to the base station device, and the base station device measures a channel state based on the received sounding reference signal. In LTE, the mobile station device periodically transmits an SRS based on a higher layer signal received from the base station device. The SRS that is periodically transmitted is referred to as a periodic SRS. In LTE, the mobile station device transmits an SRS only one time based on an SRS trigger received from the base station device. The SRS that is transmitted only one time is referred to as an aperiodic SRS.
In LTE, open loop parameters can be independently set for a transmission power control process for the periodic SRS and for a transmission power control process for the aperiodic SRS. Furthermore, in LTE, a shared TPC command is used for the transmission power control process for the periodic SRS and for the transmission power control process for the aperiodic SRS.
In 3GPP, it has been considered that for uplink coordinated communication (uplink coordinated multi-point transmission/reception), the mobile station device is configured to support multiple transmission power control processes for the aperiodic SRS (NPL 1 and NPL 2). Moreover, in a case where the mobile station device supports multiple transmission power control processes for the aperiodic SRS, it also has been considered that an open loop parameter and a TPC command should be independently set for each of the multiple transmission power control processes for the aperiodic SRS.